Chromatograph



FIG. 1 is a top, front, right side perspective view of an ornamental design for a chromatograph;

FIG. 2 is a front view thereof;

FIG. 3 is a top view thereof;

FIG. 4 is a rear view thereof;

FIG. 5 is bottom thereof;

FIG. 6 is a right side view thereof; and,

FIG. 7 is a left side view thereof. 

The ornamental design for a chromatograph, as shown and described. 